The ace up YouTube's sleeve? It probably didn't hurt much that there's been serious talk about Google acquiring YouTube for an estimated $1.5 billion. Google would bring its AdSense advertising platform to the table and content providers would (as the prior deal with Warner stipulated) take a percentage of ad revenue from ads display while people watched their videos.

Google, of course, has its own Google Video site which operates similarly to YouTube; I'd expect some sort of merger down the line, though it may be a while. Still, going legit killed the appeal of Napster; can YouTube remain top dog with its shiny new image?